world.go

package tetra3d

const (
	FogAdd         = iota // Additive blended fog
	FogSub                // Subtractive blended fog
	FogOverwrite          // Color overwriting fog (mixing base with fog color over depth distance)
	FogTransparent        // Fog influences transparency of the render
)

const (
	FogCurveLinear = iota
	FogCurveOutCirc
	FogCurveInCirc
	// FogCurveInOutCirc   //easeInOutCirc
	// FogCurveInOutBounce //easeInOutBounce
)

type FogMode int

// World represents a collection of settings that one uses to control lighting and ambience. This includes the screen clear color, fog color,
// mode, and range, whether lighting is globally enabled or not, and finally the ambient lighting level (using the World's AmbientLight).
type World struct {
	Name       string
	ClearColor Color // The clear color of the screen; note that this doesn't clear the color of the camera buffer or screen automatically;
	// this is just what the color is if the scene was exported using the Tetra3D addon from Blender. It's up to you as to how you'd like to
	// use it.
	FogColor Color   // The Color of any fog present in the Scene.
	FogMode  FogMode // The FogMode, indicating how the fog color is blended if it's on (not FogOff).
	// FogRange is the depth range at which the fog is active. FogRange consists of two numbers,
	// ranging from 0 to 1. The first indicates the start of the fog, and the second the end, in
	// terms of total depth of the near / far clipping plane. The default is [0, 1].
	FogOn           bool
	DitheredFogSize float32   // If greater than zero, how large the dithering effect is for transparent fog. If <= 0, dithering is disabled.
	FogRange        []float32 // The distances at which the fog is at 0% and 100%, respectively.
	FogCurve        int
	LightingOn      bool          // If lighting is enabled when rendering the scene.
	AmbientLight    *AmbientLight // Ambient lighting for this world
}

// NewWorld creates a new World with the specified name and default values for fog, lighting, etc).
func NewWorld(name string) *World {

	return &World{
		Name:            name,
		FogColor:        NewColor(0, 0, 0, 0),
		FogRange:        []float32{0, 1},
		FogOn:           true,
		LightingOn:      true,
		DitheredFogSize: 0,
		ClearColor:      NewColor(0.08, 0.09, 0.1, 1),
		AmbientLight:    NewAmbientLight("ambient light", 1, 1, 1, 0),
	}

}

// Clone returns a new World with the same properties as the existing World.
func (world *World) Clone() *World {

	newWorld := NewWorld(world.Name)

	newWorld.ClearColor = world.ClearColor
	newWorld.FogColor = world.FogColor
	newWorld.FogMode = world.FogMode
	newWorld.FogRange[0] = world.FogRange[0]
	newWorld.FogRange[1] = world.FogRange[1]
	newWorld.LightingOn = world.LightingOn
	newWorld.FogCurve = world.FogCurve
	newWorld.AmbientLight = world.AmbientLight.Clone().(*AmbientLight)
	newWorld.DitheredFogSize = world.DitheredFogSize

	return newWorld

}

func (world *World) fogAsFloatSlice() []float32 {

	fog := []float32{
		float32(world.FogColor.R),
		float32(world.FogColor.G),
		float32(world.FogColor.B),
		float32(world.FogMode),
	}

	if !world.FogOn {
		fog[3] = -1
	}

	return fog
}